This application is related to Japanese Patent Applications No. 2000-136215 filed on May 9, 2000, No. 2000-139027 filed on May 11, 2000, No. 2000-160813 filed on May 30, 2000, No. 2000-169156 filed on Jun. 6, 2000, and No. 2000-180239 filed on Jun. 15, 2000, the contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a vehicle air conditioning system for performing an air conditioning control based on a temperature within a passenger compartment, detected by a non-contact temperature sensor.
2. Description of Related Art
A conventional air conditioning system for a vehicle using a non-contact temperature sensor is disclosed in each of JP-A-10-197348 and JP-A-10-230728. In these conventional systems, temperatures of a passenger and in the neighborhood of the passenger are detected by an infrared sensor (non-contact temperature sensor) in which plural temperature detecting elements are arranged in a shape of a matrix, and a direction of solar radiation or intensity of the solar radiation is estimated based on their temperature signals of the infrared sensor. In the conventional system as disclosed in JP-A-10-230728, an atmospheric temperature in the neighborhood of a passenger is further estimated, and the air conditioning control is performed based on the estimated atmospheric temperature. However, in the matrix infrared sensor, when both the temperature in the neighborhood of the passenger and the temperature of a predetermined-position face skin of the passenger are detected, it is necessary to narrow a detection area of each temperature detecting element to correspond to the detection face area of the passenger in order to accurately detect the face skin temperature of the passenger. Accordingly, the number of the temperature detecting elements is increased, production cost of a control circuit of the air conditioning system is increased, and a processing time of temperature signals becomes longer.
In view of the foregoing problems, it is an object of the present invention to provide a vehicle air conditioning system with a non-contact temperature sensor having plural temperature detecting elements, which accurately detects temperature in a narrow range and shorten a temperature-signal processing time in low cost.
It is an another object of the present invention to provide a vehicle air conditioning system using a non-contact temperature sensor, in which a stable temperature environment can be obtained in the passenger compartment.
It is a further another object of the present invention to provide a correction method of a non-contact temperature sensor, for accurately detecting a temperature detecting object.
According to the present invention, in a vehicle air conditioning system, a non-contact temperature sensor is disposed to detect a predetermined region within a passenger compartment in a non-contact state using plural temperature detecting elements, and an air-conditioning state to be introduced into the passenger compartment is controlled based on a temperature signal from the non-contact temperature sensor. In this vehicle air conditioning system, the temperature detecting elements include a plurality of first elements each of which has a first temperature detecting area in the predetermined region, and a plurality of second elements each of which has a second temperature detecting area larger than the first temperature detecting area in the predetermined region. Thus, temperature in an area where a detail temperature-distribution information is necessary is detected using the first elements to be accurately detected, while the number of the entire temperature detecting elements is made smaller. Accordingly, the temperature in a narrow range can be accurately detected by the non-contact temperature sensor, and a temperature-signal processing time can be shortened in low cost.
Preferably, when a passenger is seated on a seat in the passenger compartment, the predetermined region includes the face portion of the passenger and a part around the face portion, and the non-contact temperature sensor is disposed to detect temperature of the face portion of the passenger using the first elements and to detect temperature of the part around the face portion using the second elements. Accordingly, temperature information regarding the face portion of the passenger can be accurately detected.
Further, the non-contact temperature sensor is disposed in such a manner that the face portion and a glass portion of the vehicle are overlapped from each other when being viewed from a position of the non-contact sensor to the predetermined region. Because the glass is low in thermal conductivity and a thermal capacity thereof is large, an abrupt temperature change, due to conditioned air, outside air, solar radiation, or the like, hardly occurs. Therefore, fluctuation of an average temperature of the face portion due to the temperature fluctuation of the face portion background portion becomes small, the fluctuation of the blow-out air amount and the blow-out air temperature of conditioned air become small, and a stable temperature environment is obtained in the passenger compartment.
Preferably, a control unit for controlling the air-conditioning state using the non-contact temperature sensor includes specific region detecting means for detecting a specific region where temperature is out of a predetermined temperature range among the predetermined region, and disturbance determining means which determines that there is a disturbance when the specific region moves in the predetermined region with an elapsed time. Accordingly, an outer disturbance object can be readily accurately determined, and air-conditioning operation of the vehicle air conditioning system can be accurately performed.
In addition, a reference member is disposed in the predetermined region to be set at a predetermined temperature, an initial output value of the non-contact temperature sensor, obtained by detecting temperature of the reference member at an initial time is stored, and a correction coefficient of a present output value of the non-contact temperature sensor is corrected by comparing the present output value and the initial output value. Here, the present output value is obtained by detecting temperature of the reference member at the present time. Accordingly, temperature of a temperature detecting object can be accurately detected.
Preferably, the control unit forms a temperature distribution map of the face portion and the part around the face portion based on temperature signals from the temperature detecting elements of the non-contact temperature sensor, the control unit estimates a position of the face portion within the temperature distribution map, and the control unit estimates a position of a specific portion within the face portion based on a temperature change in the estimated position of the face portion. Accordingly, the position of the specific portion can be accurately estimated.
According to an another aspect of the present invention, a non-contact temperature sensor has a plurality of temperature detecting elements each of which generates an electrical signal in accordance with an amount of infrared rays, and the non-contact temperature sensor is disposed to detect a predetermined region within the passenger compartment in a non-contact state using the temperature detecting elements. Further, a control unit controls an air-conditioning state to be introduced into the passenger compartment based on a temperature signal from the non-contact temperature sensor, the non-contact temperature sensor include a lens through which the infrared rays pass, and the lens is disposed to change a relative position with the temperature detecting elements. The control unit changes the relative position of the lens with the temperature detecting elements to switch a first state of the non-contact temperature sensor, for detecting temperature of an entire area of the predetermined region, and a second state of the non-contact temperature sensor, for detecting temperature of a part area in the predetermined region. Accordingly, a detail temperature information can be obtained in the second state.